Female
Reproductive
System
16.3 Female reproductive system
Female anatomy
•
Internal genitals :
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Ovaries
Uterine tube
Uterus
Vagina
• External genitals
(vulva):
– Labia major
– Labia minor
– Mons pubis
– Clitoris
16.3 Female reproductive system
Female anatomy: Genital tract
•
Ovaries – produce eggs and sex hormones
•
Uterine (Fallopian) tubes –
moves eggs and normal site of fertilization
•
Uterus – normal site of implantation and fetal
development
•
Cervix – ‘neck’ of the uterus that can dilate during
childbirth
•
Vagina – birth canal
VAGINAL OPENING
• Opening may be covered by a thin
sheath called the hymen
• Using the presence of an intact hymen
for determining virginity is erroneous
• Some women are born without hymens
• The hymen can be perforated by many
different events
PERINEUM
• The muscle and tissue located between the
vaginal opening and anal canal
• It supports and surrounds the lower parts of the
urinary and digestive tracts
• The perineum contains an abundance of nerve
endings that make it sensitive to touch
• An episiotomy is an incision of the perineum
used during childbirth for widening the vaginal
opening
INTERNAL GENITALIA
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The internal genitalia consists of the:
Vagina
Cervix
Uterus
Fallopian Tubes
Ovaries
VAGINA
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The vagina connects the cervix to the external genitals
It is located between the bladder and rectum
It functions :
As a passageway for the menstrual flow
For uterine secretions to pass down through the introitus
As the birth canal during labor
With the help of two Bartholin’s glands becomes
lubricated during SI
CERVIX
• The cervix connects the uterus to the
vagina
• The cervical opening to the vagina is small
• This acts as a safety precaution against
foreign bodies entering the uterus
• During childbirth, the cervix dilates to
accommodate the passage of the fetus
• This dilation is a sign that labor has begun
UTERUS
• Commonly referred to as the womb
• A pear shaped organ about the size of a clenched fist
• It is made up of the endometrium, myometrium and
perimetrium
• Consists of blood-enriched tissue that sloughs off each
month during menstrual cycle
• The powerful muscles of the uterus expand to
accommodate a growing fetus and push it through the
birth canal
FALLOPIAN TUBES
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Serve as a pathway for the ovum to the uterus
Are the site of fertilization by the male sperm
Often referred to as the oviducts or uterine tubes
Fertilized egg takes approximately 6 to 10 days
to travel through the fallopian tube to implant in
the uterine lining
OVARIES
• The female gonads or sex glands
• They develop and expel an ovum each month
• A woman is born with approximately 400,000 immature
eggs called follicles
• During a lifetime a woman release @ 400 to 500 fully
matured eggs for fertilization
• The follicles in the ovaries produce the female sex
hormones, progesterone and estrogen
• These hormones prepare the uterus for implantation of
the fertilized egg
16.3 Female reproductive system
Female anatomy: External anatomy
• Labia major – 2 large folds of fatty skin
• Labia minor – 2 small folds just inside the labia
major that contain the opening to the urethra
and vagina
• Mons pubis – fatty skin covered in coarse hair
• Clitoris – erectile organ
The ovarian cycle: The ovary
• Contains many follicles each containing an immature
egg (oocyte)
• At birth a female has ~300,000-400,000 follicles
• During the lifetime of a female only ~400 follicles mature
• One follicle matures each cycle from puberty until
menopause
• Ovulation is the monthly release of an oocyte from the
ovary when a follicle ruptures
16.4 Female hormone level
Anatomy of the ovary
16.4 Female hormone level
The ovarian cycle
• This is the formation and release of an immature
egg
• 2 phases:
- Follicular phase:
- FSH promotes the development of a follicle that secretes
estrogen
- An estrogen spike leads to a surge in LH and ovulation
around day 14 in the 28-day cycle
- Luteal phase:
- LH promotes the develop of the corpus luteum that functions
to secrete progesterone
- If pregnancy does not occur menstruation begins
16.4 Female hormone level
The uterine cycle
• A 28-day cyclic event in the uterus:
• Days 1-5: low level of estrogen and progesterone
causing the inner uterine lining (endometrium) to
disintegrate and menstruation occurs
• Days 6-13 (proliferative phase): increase in estrogen
causing the endometrium to thicken
• Day 14: ovulation usually occurs
• Days 15-28 (secretory phase): increase in
progesterone causes endometrium to double or triple
in thickness in preparation for the developing embryo.
If the egg is not fertilized then the corpus luteum
regresses and the endometrium breaks down
16.4 Female hormone level
Hormones in the ovarian and uterine phase
16.3 Female reproductive system
Female anatomy: Genital tract
16.4 Female hormone level
Fertilization and Pregnancy
• Fertilization – union of a sperm and egg
nucleus normally in the oviduct to form a
zygote
• Pregnancy – begins with implantation
usually ~6 days after fertilization
16.5 Control of reproduction
Some common birth control methods
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Abstinence – not engaging in sexual intercourse
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Hormonal control:
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Barrier methods:
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Birth control pills: blocks FSH and LH release to stop follicular development and
ovulation
Contraceptive injections: injection of hormones (progesterone and/or estrogen) to
stop ovulation
Contraceptive implants: synthetic progesterone to prevent ovulation
IUD: small plastic piece inserted into the uterus to prevent implantation
Condom (male and female): blocks fertilization
Diaphragm: soft latex cup that covers the cervix so sperm cannot enter the
uterus
Sterilization:
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Vasectomy: cutting and sealing the vas deferens
Tubal ligation: cutting and sealing the oviducts
• Vagina = “birth canal”
– Elastic tube-like
pathway
– 4-5” long
– At rest, walls of vagina
touch
• During arousal, they
expand to allow penis to
enter
• If not ready/aroused,
walls of vagina will tear
– Capable of stretching to
allow birth
CERVIX
VAGINA
Leads to CERVIX
- “neck of the uterus”
- Opening is small,
dilates (“opens”) to
allow passage of baby.
• UTERUS
– Strong elastic
muscle; about the
size of a fist
– Primary fxn – hold &
nourish developing
embryo & fetus
– Endometrium
• Inner lining of uterus
• Rich supply of blood
vessels
– Builds up w/blood
tissue to prepare for
a possible pregnancy
UTERUS
The parts on the inside are:
Uterus
• Sometimes called the womb.
• Muscular organ about the size of a
pear.
• Where developing baby, called a
fetus, grows and is fed.
• Where the period comes from.
Cervix
• The lower part of the uterus.
• Makes mucus to keep sperm alive.
• Has opening where sperm enter
uterus and where the baby comes
out of the uterus.
Vagina
• Warm, soft, moist
passageway joining
outside and uterus.
• Fallopian Tubes
– Tubes on each side
of the uterus
– Leads to ovaries
– Extremely narrow;
lined with cilia
(similar…?)
FALLOPIAN
TUBES
• Fimbriae
FIMBRIAE
• Finger-like projections at the end of
the fallopian tubes
• Surrounds the top part of each
ovary
• Gathers ovum into tube
• Fertilization usually occurs in the
widest part of the fallopian tube
OVARIES
• Female sex
glands/organs
• Situated on both
sides of the uterus;
end of fallopian
tubes
• 2 main functions
– House ova
– Produce female sex
hormones
• Estrogen &
Progesterone
OVARY
The parts on the inside are:
Fallopian tubes
• Narrow tubes between the uterus
and the ovary.
Ovaries
• Glands that make egg cells and
female sex hormones.
Ovulation
• Process of releasing one mature ovum
each month into that ovary’s fallopian tube
• 2-300,000 immature ova in ovaries at birth
• Hormones from pituitary cause ovaries to
begin producing female sex hormones
• Ova begin to mature
• Ovum can live about 2 days in fallopian
tube
• One sperm will enter ovum =
fertilization/conception
MENSTRUATION
• Each month, uterus
prepares for possible
pregnancy
– Hormones cause
thickening of
endometrium
– If ovum is fertilized, it
moves into the uterus
and may burrow into
this lining
– Will divide millions of
times over 9-10
months
Menstrual Period
• If the ovum is not
fertilized – it doesn’t
attach to the uterine
lining/endometrium
• Muscles of the uterus
contract  lining breaks
down (“cramps”)
• Lining passes through the
cervix into the vagina and
out of the vaginal opening
Menstruation
• Process of shedding the lining of the
uterus
• Usually lasts 4-7 days (may be shorter or longer depending
on the female’s individual cycle)
• Regulated by hormones
• 2-3 tablespoons of blood
• Rest of flow is other tissue that makes
up the endometrium
– Blood and tissue are not needed, person
should not be weak or ill from loss
– After period (“menses”), cycle begins
again.
Menstruation cont…
• Most females begin menstruation between
10-15
• As with males, many hormonal changes are
occurring, so the body may take a couple of
years to adjust
• Cycle may be irregular
Menopause
– Ceasing of menstruation
– Between 45-50
• Hormones control the cycle
– Nutrition, stress & diet can influence cycle
Menstrual Health Care
• Should not be an odor from vagina at any
time
• Menstrual flow should not have an odor until
it mixes with air
Products
– Absorb menstrual flow
– Sanitary napkin/panty shield
• Worn outside the body
• Should be changed every 3-4 hours, depending on the
heaviness of flow
– Tampons
• Worn inside the body/vagina
• Must be changed frequently to avoid risk of infection